Selector<T, R> class

A specialized observable that derives its value from another observable using a selector function.

The Selector automatically updates whenever the source observable changes, but only notifies its own listeners if the selected value actually changes.

Inheritance
Available extensions

Constructors

Selector.new(Observable<T> _source, R _selector(T), {EqualityFunction<R>? equals, ErrorCallback? onError})
Creates a new Selector that derives its value from the source observable.

Properties

hashCode int
The hash code for this object.
no setterinherited
isDisposed bool
Whether this object has been disposed.
no setterinherited
runtimeType Type
A representation of the runtime type of the object.
no setterinherited
selector → R Function(T)
The selector function used to derive the value.
no setter
source Observable<T>
The source observable this selector depends on.
no setter
value ↔ R
value method.
getter/setter pairinherited

Methods

addDisposeCallback(VoidCallback callback) → void
Add a callback to be executed during disposal.
inherited
addListener(VoidCallback listener) → void
addListener method.
inherited
addSubscription(StreamSubscription subscription) → void
Add a stream subscription to be cancelled during disposal.
inherited
combineWith<U, R>(Observable<U> other, R combiner(T, U)) Observable<R>

Available on Observable<T>, provided by the ObservableSelector extension

dispose() → void
dispose method.
override
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
read() → R
read method.
inherited
removeListener(VoidCallback listener) → void
removeListener method.
inherited
select<R>(R selector(T)) Observable<R>

Available on Observable<T>, provided by the ObservableSelector extension

selectR> method.
setDebounceTimer(Timer timer) → void
Set or update the debounce timer.
inherited
setValueDebounced(R newValue, Duration delay) → void
setValueDebounced method.
inherited
throwIfDisposed([String? operation]) → void
Throw if this object has been disposed.
inherited
toString() String
A string representation of this object.
inherited
validateEmail() Observable<String?>

Available on Observable<String>, provided by the StringValidation extension

validateEmail method.
validateLength({int? min, int? max}) Observable<String?>

Available on Observable<String>, provided by the StringValidation extension

validateLength method.
watch() → R
inherited
withSelector(R newSelector(T)) Selector<T, R>
Updates the selector function and recomputes the value.

Operators

operator ==(Object other) bool
The equality operator.
inherited